1. Field of the Invention
The present invention relates to a card comprising an integrated circuit module (hereinbelow called an "IC module"), and more particularly to a card and processing device for it wherein the IC module can be rapidly read, while preventing fraudulent use.
2. Description of the Related Art
IC cards are conventionally known in which an IC module comprising an electrically rewritable non-volatile memory (hereinbelow called an "EEPROM") and microprocessor is incorporated in a plastic card.
Such IC cards are widely used for example in the management of personal information by banks on account of their properties of having larger memory capacity than conventional magnetic cards and of being able to be read and written repeatedly.
Recently in particular, hybrid cards have appeared in which the IC card incorporates in combination an optical memory unit whereby a larger quantity of information can be stored than can be stored in the IC module, and/or a magnetic stripe for convenient data reading.
However, the present situation is that standards regarding such IC modules have not yet been fully established. Specifically, although standards are being unified regarding the data transfer rate and mode of arrangement of contacts of the IC module, no steps have been taken to unify standards regarding clock pulse frequency etc.
Consequently, in a device such as a bank card reading device that handles not only its own cards but also cards issued by other organizations, there are installed beforehand in the interior of the device read/write units corresponding to each standard, and the type of card is usually identified by a "cut and try" system.
Such a cut and try system is a technique in which a read/write unit matching the card is sought by a process of trial and error. For example, issued Japanese Patent Publication (Kokoku) HEI 4-38080 discloses an IC card read/write device wherein clock pulses of a plurality of frequencies are generated from a single clock pulse generating means and if the output signal of the IC card is inappropriate the clock pulse generating means is changed over.
However, when a cut and try system typified by the prior art is employed, the problem arises that time is required in specifying the read/write unit corresponding to the IC module.
In particular, the number of times of trial and error increases with increase in the number of read/write units installed, so the time required for cut and try also increases.
As a result, when there are a large number of different read-write units, how to shorten the time for reading/writing the IC module has come to present a serious problem.
Also, with such IC modules, apart from the delay of the reading/writing time referred to above, there is a security problem.
In more detail, such an IC module is a self-complete type module that is capable of exchanging the data with the read/write unit by itself; furthermore, in general, the IC module can easily be fitted or removed, so this invites remodeling of the card by replacing the IC module with another IC module.
For this reason, consideration has been given to providing the IC module itself with a security mechanism such as a rewriting prevention function. However, it is not practicable to provide such a security mechanism for compact IC modules, which are of small size and light weight.